Looks like a bug…
having …
_nic = new EthernetENC28J60(SPI.SPI_module.SPI1, Pin.P1_5, Pin.P0_1, Pin.P0_10, 10000);
using somewhere in the code:
_nic.NetworkInterface.RenewDhcpLease();
calling RenewDhcpLease() generates pulses on the clock line of SPI2 while ENC28 is connected to SPI 1
using fix-firmware 9.2.10.3